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Tuesday, August 7, 2012

Curiosity is RTG powered and some NASA thoughts

Curiosity is powered by a Uranium-238 radioisotope thermoelectric generator. Yes, that means Curiosity is powered by nuclear power but is relatively safe as long as the radioactive material is handled safely at the end of its lifetime of power generation.

RTGs were developed in the late 1950s in the United States by Mound Laboratories in Ohio jointly with the Atomic energy Commission. They are designated as Systems for Nuclear Auxiliary Power or SNAP, we like acronyms, and the first one used was SNAP-3 on the US Navy Transit 4A spacecraft in 1961. This was the sat navigation system used to provide accurate positioning for our Polaris Missile Submarines.

The Russians have used RTG for lighthouse power in remote areas although the US was the first to use one on land at uninhabited Fairway Rock in Alaska in1966.

Currently RTGs sit on the moon as the result of their use on Apollo 12, 14, 15, 16, and 17. They were part of the power pack necessary for ALSEP, Apollo Lunar Surface experiment Packages, and were designated as SNAP-27 and powered the long lived part of the Lunar Lander package. These stations transmitted information about moonquakes and meteor impacts, lunar magnetic and gravitational fields, the Moon's internal temperature, and the Moon's atmosphere for several years after the missions. After ten years, a SNAP-27 still produces more than 90% of its initial output of 70 Watts. 70 Watts doesn't sound like a lot but it was back then. There are currently two Viking missions with RTGs sitting on Mars.

The fuel capsule, containing 3.8 kilograms (8.36 pounds) of fuel, was carried to the Moon in a separate Fuel Cask attached to the side of the Lunar Lander. The fuel cask provided thermal insulation and added structural support to the fuel capsule. On the Moon, the Lunar Lander pilot removed the fuel capsule from the cask and inserted it in the RTG. Yes the Astronaut loaded the RTG which was inactive until landing.

Because an RTG is used in a spacecraft not intended for return to earth normally storage of the spent plutonium-238, it is non explosive by the way, is not an issue but there was one incident that is rarely talked about. When Apollo 13 returned to the earth they used the Lunar Lander as a life raft until just before reentry when the Lander was discarded and the Command Module was used for reentry. The Lunar vehicle mostly burned up on reentry but the plutonium-238 went to the bottom of the South Pacific Ocean near the Tonga Trench and has never been recovered. By the way NASA referred to it as the Lunar Module (LM) but the flyboys called it a Lander for obvious reasons.

Spirit and Opportunity, 2004 Mars Rovers, were powered by solar energy because they were small. All long range unmanned missions are usually powered by an RTG for a reliable source of power. It has been a long running issue with the anti-nuke people over the years but thankfully other than 13s LM SNAP-27 no real issues have resulted although it is unknown if RTGs were on any failed missions out of Vandenberg in California which is a military launch site for covert and private launches of military equipment.

The RTG on Curiosity is a new design from Boeing and generates 125 watts of power from 2000 watts of thermal energy at the start of the mission. it has a life of 14 years but Curiosity is unlikely to make it that long. The Multi-Mission Radioisotope Thermoelectric Generator or MMRTG is 4 times more powerful than the solar powered Rovers from 2004 and also provides warmth for sensitive equipment and actually pumps fluids to some.

A manned mission to Mars will require something different the the current MMRTG technology and solar will not cut it either. The spacecraft in transit to Mars will require a separate and more powerful source of power that will have to be nuclear in nature with a backup in case of problems. The Mars Lander will also require special power depending on duration of the mission on the surface.

On Apollo the Service Module provided electrical power with three fuel cells built into the North American Aviation designed Command and Service Module combo but they had limited lifetime sufficient for Lunar missions. The fuel cells provide power for heat, electricity and potable water. This system would not be capable of handling any long duration manned mission like Mars.

Our dipshit politicians, in both parties, along with NASA incompetence have allowed us to lose our way in the space program. The Shuttle was not a bad idea but even a decent idea badly managed is not good and add to that the needless deaths of 14 Astronauts and two lost Shuttles and even I have to admit NASA got what it deserved in so many ways.

Challenger was launched below 48 degrees which was the minimum requirements for a warm launch site like Kennedy (I hate calling it Canaveral). They launched at 42 degrees F with icicles hanging off the Shuttle despite knowing that previous launches below 48 resulted in solid booster leaks. Rubber O-rings have several key properties one of which is a known expansion rate given a starting temperature of the compound. They played Russian Roulette with the lives of 7 Astronauts and the Astronauts lost.

Columbia was even worse. They knew the wing was hit by foam from the Martin Marietta external tank yet they never sent any of crew out for a check and ALL Shuttle command crew are EVA qualified and have equipment available to perform an inspection. They then played Russian Roulette with these 7 Astronauts and Columbia disintegrated because on reentry to plasma generated by compression and heating of even a thin
atmosphere found its way into the wing and weakened the structure and killed 7. One NASA dipshit even claimed they never worry about reentry on NASA television but was quickly shut up because the simple truth is if anything goes wrong on reentry the spacecraft is severely compromised and unlikely to survive plus their is the communication blackout cause by ionization caused by the compression and heating of the atmosphere.

This is what happens when mediocrity, which is government hack, meets engineering requirements and the hacks win. First rule of manned spaceflight is the book is it. You follow the book and never violate the procedures and I mean never unless something untoward happens and then you check the book for a process that might work and improvise if necessary.

Even on Apollo NASA violated the book and killed 3 Astronauts in the Apollo 1 pad fire. I look at NASA sometimes and wonder where we went wrong but I deeply believe in the manned space program but sometimes it is hard to justify even if the NASA budget is less than 1% of the total federal budget. Somehow I think the Defense budget could have spared a few billion here and there. NASA has been a bureaucratic mess since just before Apollo 10 when the hacks realized we were going to pull it off and they weaseled their way in with the help of your local elected officials and the hammer of budget cuts.

Obama was quick to jump on the early success of Curiosity but he, along with Congress, destroyed the careers of many of our best engineers in Florida because the men and women that get the vehicles into orbit and prepare them and repaired the Shuttle were among the best and the brightest and Obama lied to them like every politician lies to them. Men and women with 20-30 plus years experience in missile and space exploration vehicles were just laid off. That is like Apple firing everybody in the company that knows who to put the product together so it will work and can be delivered to the consumer.

Maybe we will wake up when the Chinese and their lead painted spacecraft returns humans to the moon. I should stop now because it infuriates me. How the hell did we go from putting a man on the moon to outsourcing to Russia the sending of our people to the International Space Station? The answer is stupidly simple. Political correctness, political expediency, and political cowardliness and a NASA where the bog pieces always seemed to float to the top the quickest. (think cesspool)

11 comments:

Anonymous
said...

Yes, the failure of will, let alone common sense, utterly guts me. I do cling to the hope that those of us who value knowledge shall yet find some way to pass it onward to the younger generation. As you yourself surely know, they aren't altogether a write-off.

I had a supervisor who worked for a subcontractor on Apollo. When the fire happened NASA went looking for someone to blame for their own stupidity. It wasn't until years later they admitted their mistake.

Unless something changes, and I don't think it will. Those who colonize the solar system will not be speaking English.

We seem to be obsessed with overthrowing governments and playing UN cop. Instead of exploration it seems we are the promoter of death and destruction, we will get what we deserve as we are used and thrown on the ash heap of history. NYF

Great Rant. It is what happens when the "majority rules". PC is a weapon used to pander to masses with the end result being the supremacy of mediocraty and the demonization of personal achievement and excellence.

I don't know if anyone knows the answer to these human problems. I don't even know if it exists. I might be wrong, but I think that our solutions for organisation are just too primitive to do such things unless there is a direct visible incentive for all of those twitching palms. Instead everything seems to happen due to some form of diffusion where a diverse range of incentives keep on causing this brownian motion like drift of technology after going back and forth for some time. That's why I think there is an inevitability to quite a few things such as human space exploration and maybe even colonisation. It's a bit boring to watch it happen, I'm hoping that the heat will get turned up and the process will happen faster.

>>> First rule of manned spaceflight is the book is it. You follow the book and never violate the procedures and I mean never unless something untoward happens and then you check the book for a process that might work and improvise if necessary. <<<

I'd never thought of it that way. It makes a lot of sense to do that, but I have to ask this, did it ever bother you that there might be a better way to do things than the Book? What if the Book itself is wrong? (yeah I'm a heretic :)

NASA never admitted their mistake on the Apollo 1 pad fire publicly. North American bent over and took one for the program per usual.

The inward opening egress hatch was forced on the contractor by a NASA dipshit because of the Mercury 7 Liberty Bell sinking incident in July of 1961. The hatch blew open on landing and there were some accusations Gus blew the hatch but no Astronaut was ever more by the book than Grissom. He would have not blown the hatch unless he was sinking.

All of our recoveries were down in the ocean because in general it is actually safer or was then because of consistency of landing surface as in flat, despite waves, and buoyant salt water. This was primarily because it was basically impossible to accurately predict where a spacecraft would land after reentry into the atmosphere because reentry and landing were essentially uncontrollable after started. The only control was minor corrections by computer for yaw, pitch, and roll.

In those days we still had to compute initial orbit from launch by hand and by that a mean mechanics professors and mathematicians did the raw calculations so with reentry being just a deorbit burn and a blazing path through to the ocean it was a little like a crap shoot on landing.

Besides, a land based landing in the US has all kinds of additional hazards like landing in a populated area. It would have been quite a surprise in Gus landed in somebodies living room. Besides Astronauts were always quarantined after landing for medical inspection and particularly for Lunar missions.

We violated many procedures on Apollo 1 but the biggest was we never pressure tested a vehicle with Astronauts on board using pure oxygen because of inherent hazards. One spark and it could get ugly and at 15 psi Godzilla could not have opened the Apollo 1 hatch inward but there was one more problem not mentioned.

Apollo 1 was generation 1 of the Apollo Command module and was not designed to connect with the Lunar Module so there was no egress hatch to access the LM although it is doubtful they could have gotten out that way either. The fire built up so much internal pressure it blew "out" the hatch but they were dead by then.

We pushed it because we were worried the Russians would beat us to the moon. They had the big launch vehicles and our Saturn V was not quite ready yet. We did not know that Sergei Korolev, the father of the Russian Space program, had died after a routine operation in Russia. Korolev was a brilliant man.

It will take a leader with vision to put this country back on the right path and neither the incumbent nor the challenger have that sort of vision.

A Mars mission would require a multinational approach because both the Mars Lander and Mars mission spacecraft will have to be built in orbit or at worst built in sections and assembled in orbit because they will by necessity be big.

I doubt it will happen in my lifetime. There is no apparent need or desire or courage to do it since every special interest group has there collective hands out wanting something for nothing.

The book is the process or the set procedures used during all parts of a manned space flight. If you ever watched mission control you will see everyone with a bound folder of some kind. It is the process or the book for this particular flight.

It is not how you build or design a spacecraft but how a particular mission is to be handled and the primary goal of all manned flight is crew safety. More than likely, depending on where you worked, you know or have met the crew and the book is there to prevent casual skipping of steps or procedures that might result in omissions or errors that endanger the crew safety. Challenger is a classic example of a deliberate example of not following the book and Launch Directors had done it before and gotten away with it but not this time.

They had been warned multiple times by Morton Thiokol, designers and builder of solid boosters, they were violating safety rules by launching below 48 degrees Fahrenheit. They were lucky the other times because the O-ring leaked away from the Shuttle's External Tank. It was basically negligent homicide and I have a friend at Martin Marietta Manned Space Systems in Michaud Louisiana who said so when it happened. They built the External Tank for Shuttle there.

We would still be flying the Shuttle if not for the Challenger and Discovery losses in my opinion since Shuttle usage would have been lower and despite what they have said the surviving Shuttles were certainly space worthy for quite some time but politically canceling the Shuttle program helped with left wing dipshits.

NASA is both out of touch with reality and poorly managed except for JPL. NASA had to be forced into the last repair of the Hubble Space Telescope because it had no intention of repairs and upgrades for one of the most successful platforms ever despite launching the Hubble with bad optics which the Shuttle repaired.

Isn't it funny to even ironic that NASA, the DOD, and the US Air Force could design build and launch the XB37 mini shuttle without any budgetary constraints. Nobody seems to have a clue what it cost or actually what the heck it is doing but it is certainly not taking, "one small step for man, one giant leap for mankind," or doing anything for anyone but the military which is sad.

>>> The book is the process or the set procedures used during all parts of a manned space flight. If you ever watched mission control you will see everyone with a bound folder of some kind. It is the process or the book for this particular flight.

It is not how you build or design a spacecraft but how a particular mission is to be handled and the primary goal of all manned flight is crew safety <<<

Ah I see. I didn't know that. Thanks for teaching me this. :)

It makes logical sense, for something that dangerous it makes to really does make a lot of sense to have a strict codified operating protocol. I've noticed that humans might be creative in emergencies, but they suck at the routine. When you have so many variables and so many things that can go wrong. Working without a protocol probably has worse odds than going out gambling in mafia era Las Vegas.

>>> Challenger is a classic example of a deliberate example of not following the book and Launch Directors had done it before and gotten away with it but not this time.

They had been warned multiple times by Morton Thiokol, designers and builder of solid boosters, they were violating safety rules by launching below 48 degrees Fahrenheit. <<<

I read up about this after I came across this bit in Feynman's memoirs. This quote has always stuck with me;

> For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.

>>> They were lucky the other times because the O-ring leaked away from the Shuttle's External Tank. It was basically negligent homicide and I have a friend at Martin Marietta Manned Space Systems in Michaud Louisiana who said so when it happened. They built the External Tank for Shuttle there. <<<

That's just disgusting and unfortunately it's barely the start. Have you ever read about Vladimir Komarov's fate? It is sickening. (warning: the link contains a very graphic image of what remained of that brave man)

>>> We would still be flying the Shuttle if not for the Challenger and Discovery losses in my opinion since Shuttle usage would have been lower and despite what they have said the surviving Shuttles were certainly space worthy for quite some time <<<

There just wasn't any incentive for them as an institution to switch out of it. I don't know if I'm right, but if I remember correctly the military bifurcated its missions at some point from NASA. That probably explains a lot about why everything stalled.

>>> but politically canceling the Shuttle program helped with left wing dipshits. <<<

Never really understood that. It's one thing to phase something out, but to demand its cancellation for some nebulous hand waving is disturbing. Decisions shouldn't be made like that.

>>> NASA is both out of touch with reality and poorly managed except for JPL. <<<

>>> Isn't it funny to even ironic that NASA, the DOD, and the US Air Force could design build and launch the XB37 mini shuttle without any budgetary constraints. Nobody seems to have a clue what it cost or actually what the heck it is doing but it is certainly not taking, "one small step for man, one giant leap for mankind," or doing anything for anyone but the military which is sad. <<<

I actually find it to be delightful, because now that they have shown it can be done and made that beautiful, beautiful machine with a level of funding that no one else can match. (at least right now) All of that beauty is going to trickle down to us mere mortals over the next few years or decades. Case in point is the origin of silicon valley [1], which apparently started out due to electronic intelligence work during WW2 and subsequent cold war efforts. It's that diffusion at work.

I guess you know this better than anyone, but it never ceases to amaze me how connected these two worlds are. I doubt it that a lot of technology come to the market this fast if it hadn't been for the expansive DoD budget. I don't know if it's a bad thing but that shadow permeates everything and changes everything.

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Okay, I have a silly question this time, do you think that Mr. Armstrong said "a man" or just "man" when stepping off the lander? I find it amusing to think that one of the most important sentences ever said might have been garbled.

The cause of the fire was not the pure oxygen in the CM but it really enhanced the fire. The problem was they should not have been in the CM when they did a 15 psi pressure test. That was a violation of procedure and the egress hatch was a NASA demand.

Apollo was not going to fly with a pure oxygen environment and neither was Apollo 1 initially. We were rushing and cutting corners.